The subject invention generally relates to a printed circuit board (PCB) assembly that eliminates the need for a stiff structure for the PCB housing by mounting a stiffener board directly to the PCB.
Conventional designs for vehicle sensor assemblies, such as safety restraint modules for example, required a very stiff housing unit for a printed circuit board (PCB). The stiff housing unit is required to provide accurate transmission of crash signals from a vehicle to sensors mounted on the PCB. Further, the housing unit supports the PCB in such a manner that the sensors are prevented from receiving false crash signals caused by standard vehicle vibrations. The housing unit also includes an electromagnetic interference (EMI) wall that prevents adjacent electrical systems from interfering with the operation of the PCB.
Traditionally, a plurality of mounting components are needed to secure the PCB to the housing unit and to secure the housing unit to a vehicle structure. A typical configuration requires a plurality of screws to fasten the PCB to the housing unit. Screws are also required to attach a cover to the housing unit. The housing unit is mounted to the vehicle with a bracket assembly. Screws are required to attach the housing to the bracket assembly and are required to attach the bracket assembly to the vehicle.
This configuration has several disadvantages. The numerous additional mounting components increase the possibility that the PCB will not be properly secured within the housing unit. If the PCB is not properly secured or if the screws loosen over time, system accuracy decreases because crash signals will not be properly received by the sensors mounted on the PCB. Further, these additional mounting components increase the overall component cost, manufacturing cost, and assembly time for the system.
Accordingly, there is a need for a more efficient method and apparatus for securing a PCB and sensor assembly to a vehicle, which provides adequate protection for sensors and reduces overall vibrations, as well as overcoming the other above-mentioned deficiencies in the prior art.